Arrhythmias Flashcards
what is p wave
atrial depolarization
what is PR segment
time for impulse to travel from atria to ventricles
what is QRS wave
ventricular depolarization
what is ST segment
end of ventricular depolarization, start of repolarization
what is T wave
repolarization of ventricles
what is U wave
may indicate hypo- (abnormal)
what QT segment
total time from QRS complex to end of T wave (depolarization to repolarization)
what is normal sinus rhythm
normal
EKG of sinus tachycardia
HR greater than 100 bpm
EKG of sinus bradycardia
HR less than 60 bpm
what is sinus arrest
SA node cease fire for a short period
EKG of sinus arrest
loss of 1 or more P waves associated with QRS
what is premature atrial contraction (PAC)
extra contractions of the atria muscles
EKG of PAC
P waves may be partially or completely hidden by T waves
what is atrial flutter
electrical rhythms travel in a loop mostly in the right atrium
EKG of atrial flutter
P waves “saw tooth” followed by QRS
what is atrial fibrillation
random electrical impulses from ectopic sites around the atria
EKG of a. fib.
no P waves, irregular narrow QRS complex
what is 1st degree AV block
slowed electrical signals, all reach ventricle
what is 2nd degree AV block
missed ventricular contractions
what is 3rd degree AV block
no transmission to ventricles
EKG 1st degree
longer PR interval
EKG 2nd degree
long PR wave and P wave, not all P waves followed by QRS complex
EKG 3rd degree
irregular but slow QRS
what is bundle branch block
interference with conduction of one bunch branch , one ventricle usually
EKG of bundle branch block
broader QRS complex
what is ventricular tachycardia
single strong firing site in one of the ventricles
EKG of ventricular tachycardia
wide and distorted QRS complex, P wave absent
what is ventricular fibrillation
multiple weak ectopic sites in the ventricles
EKG of ventricular fibrillation
no identifiable P waves, T wave, or QRS complex
what premature ventricular contraction (PVC)
prematurely activated ventricles by ectopic sites in one of the ventricles
EKG of PVC
absent P wave, widened distorted QRS, premature beats
